Communications connector with crimped contacts

ABSTRACT

A communications connector with a flexible printed circuit board is provided. The flexible printed circuit board is electronically and mechanically connected to the plug interface contacts of the jack near the plug/jack interface, in order to provide effective crosstalk compensation. The flexible printed circuit board has fingers at one end allowing it to flex as individual plug interface contacts are depressed when a plug is installed into the jack. The flexible printed circuit board, or a flexible portion of a printed circuit board, is provided with elongated extensions for certain conductors to accommodate the connection of six-contact or eight-contact plugs to the connector.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 60/699,823 filed Jul. 15, 2005. This applicationincorporates by reference in their entireties U.S. patent applicationSer. No. 11/014,097, filed Dec. 15, 2004; U.S. patent application Ser.No. 11/055,344, filed Feb. 20, 2005; U.S. patent application Ser. No.11/078,816, filed Mar. 11, 2005; U.S. patent application Ser. No.11/099,110, filed Apr. 5, 2005; U.S. Provisional Application No.60/587,416, filed Jul. 13, 2004; U.S. Provisional Application No.60/637,024, filed Dec. 17, 2004.

FIELD OF THE INVENTION

The present invention relates generally to electrical connectors, andmore particularly, to a communication jack having crimped contactssecured to a flexible printed circuit.

BACKGROUND OF THE INVENTION

In the communications industry, as data transmission rates have steadilyincreased, crosstalk due to capacitive and inductive couplings among theclosely spaced parallel conductors within the jack and/or plug hasbecome increasingly problematic. Modular connectors with improvedcrosstalk performance have been designed to meet the increasinglydemanding standards. Many of these improved connectors have includedconcepts disclosed in U.S. Pat. No. 5,997,358, the entirety of which isincorporated by reference herein. In particular, recent connectors haveintroduced predetermined amounts of crosstalk compensation to canceloffending near end crosstalk (NEXT). Two or more stages of compensationare used to account for phase shifts from propagation delay resultingfrom the distance between the compensation zone and the plug/jackinterface. As a result, the magnitude and phase of the offendingcrosstalk is offset by the compensation, which, in aggregate, has anequal magnitude, but opposite phase.

Recent transmission rates, including those in excess of 500 MHz, haveexceeded the capabilities of the techniques disclosed in the '358patent. Thus, improved compensation techniques are needed.

BRIEF DESCRIPTION OF FIGURES ILLUSTRATING PREFERRED EMBODIMENTS

FIG. 1 is a front perspective view of a communications jack;

FIG. 2 is an exploded perspective view of a contact assembly showing theuse of a printed circuit board having a flexible portion;

FIG. 3 is a plan view of a flexible portion of a printed circuit board;

FIG. 4 is a perspective view of an upper conductive trace of theflexible portion of FIG. 3;

FIG. 5 is a perspective view of a lower conductive trace of the flexibleportion of FIG. 3;

FIG. 6 is a cross-sectional view along the line 6-6 of FIG. 3;

FIG. 7 is a cross-sectional view along the line 7-7 of FIG. 3;

FIG. 8 is a plan view of a printed circuit board showing a flexibleportion and a rigid portion;

FIG. 9 is a diagram showing a side view and a plan view of jack contactpoints of a flexible portion of a printed circuit, with first and eighthconnection extensions shown in extended positions;

FIG. 10 is a diagram showing a side view and a plan view of jack contactpoints of a flexible portion of a printed circuit, with first and eighthconnection extensions shown in bent positions;

FIG. 11 is a side cross-sectional view of a communications jack showingthe attachment of a flexible portion of a printed circuit board to pluginterface contacts;

FIG. 12 is a view of the detail “A” of FIG. 11;

FIG. 13 is a side cross-sectional view of a communications jack showingthe bending of plug interface contacts upon insertion of a six-contactplug;

FIG. 14 is a view of the detail “B” of FIG. 13;

FIGS. 15-17 are step-by-step side views showing the attachment of aflexible portion of a printed circuit board to crimped and welded pluginterface contacts;

FIG. 18 is a detailed view showing the jack contact point of a flexibleportion of a printed circuit board held within a crimped and welded pluginterface contact;

FIG. 19 is a side view of a plug interface clip contact; and

FIG. 20 is a side view of a plug interface clip contact with a flexibleprinted circuit clipped to the contact.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a perspective view of a communications jack 10 according toone embodiment of the present invention. The jack 10 includes a mainjack housing 12 and a rear jack housing 14 attached to the main jackhousing 12, for example via housing clips 16. The rear jack housing 14may be provided with passageways for insulation-displacement contacts(IDCs) 18 (shown in FIG. 2). A wire cap 20 provides an interface to atwisted pair communication cable. Alternatively, a punch-down block maybe incorporated into the communications jack 10. The main jack housing12 comprises a receptacle 22 for receiving a communications plug, andplug interface contacts 24 within the receptacle 22 make contact withcontacts of the plug.

The plug interface contacts 24 are held within a contact carrierassembly 26 shown in FIG. 2. The contact carrier assembly 26 comprises acontact sled 28 and a vertical support 30 adapted to hold a printedcircuit board (PCB) 32. The printed circuit board 32 comprises aflexible portion 34 having jack contact points 36 for attachment to theplug interface contacts 24. The PCB 32 further comprises a rigid portion38 to which the IDCs 18 are electrically and mechanically attached (forexample, via compliant pins). The PCB 32 provides electrical connectionbetween the plug interface contacts 24 and the IDCs 18, and furtherprovides crosstalk compensation for communication signals travelingthrough the communications jack 10.

A plan view of the flexible portion 34 of the PCB 32 is shown in FIG. 3.Jack contact points 36 a-36 h correspond to first through eighth pluginterface contacts 24. Each of the first through eighth jack contactpoints 36 a-36 h has a corresponding conductive trace 1-8 on the PCB 32.In the plan view of FIG. 3, conductive traces along the top of theflexible portion 34 are shown with solid lines, and conductive tracesalong the bottom of the flexible portion 34 are shown with dotted lines.

The compensating circuitry of the PCB 32 is divided into zones similarlyto the division shown in pending U.S. patent application Ser. No.11/078,816 filed on Mar. 11, 2005. Specifically, the compensatingcircuitry of the present invention is divided into six Zones, A-F, asdescribed in the '816 application, and further incorporates a seventhzone, Zone G.

Zone A is a transition zone from the jack contact points 36 a-36 h tothe near-end crosstalk (NEXT) compensation zone.

Zone B is the NEXT compensation zone.

Zone C is a transition zone from the NEXT compensation zone to the NEXTcrosstalk zone.

Zone D is a compensation zone to compensate for the jack contacts.

Zone E is a NEXT crosstalk zone.

Zone F is a neutral zone which connects the NEXT crosstalk zone to IDCsockets 40 as shown in FIG. 8.

Zone G is a variable compensation zone which reduces NEXT compensationas frequency increases.

FIG. 3 shows the approximate lengths of Zones A, B, C, and E in inches.

Within Zones B, D, and F, some conductive traces have capacitive platesthat allow for capacitive compensation between conductors. Thesecapacitive couplings are labeled in FIG. 3 as “C_(x,y)” where x is thecorresponding conductive trace along the top of the flexible portion 34and y is the corresponding conductive trace along the bottom of theflexible portion 34 that is capacitively coupled at that coupling. Forexample, C_(2,5) as shown in FIG. 3 is a capacitive coupling between thesecond conductive trace on the top and the fifth conductive trace on thebottom.

All of the conductive traces except the first, the seventh, and theeighth transfer between the top and bottom of the flexible portion 34through conductive vias 46 a-g as shown in FIGS. 3-5.

The flexible portion 34 of the PCB 32 of the present inventionincorporates additional features that help to accommodate the use ofeither six- or eight-contact plugs in the communications jack 10. Asshown in FIG. 3 and as described in more detail below, elongatedconnection extensions 42 a and 42 h are provided for the first andeighth jack contact points 36 a and 36 h. Further, first and secondslits 44 a and 44 b are cut into the flexible portion 34 to allow theelongated connection extensions 42 a and 42 h to bend more than theconnection extensions of the second through seventh jack contact points36 b-36 g.

FIGS. 6 and 7 show cross-sectional views of the flexible portion 34,respectively, along the lines 6-6 and 7-7 of FIG. 3. FIG. 6 shows across-section through a contact point via 48 where the first jackcontact point 36 a is connected to the first plug interface contact 24.The cross-section shows a flexible core 50 manufactured, for example, ofKAPTON polyimide film. Contact pads 52 are provided along the top andbottom layers in the area of the jack contact points 36. The via 48 isconductive and may be copper plated. FIG. 7 shows a cross-sectionthrough connection extensions 42 a and 42 b, respectively associatedwith the first and second conductors as shown in FIG. 3. Each of thecross-sections shows a flexible core. A trace 1 associated with thefirst conductor is shown on the bottom layer in FIG. 7, and a trace 2associated with the second conductor is shown on the top layer.

FIG. 8 is a plan view of the printed circuit board 32 showing theflexible portion 34 and the rigid portion 38. The rigid portion includesthe IDC sockets 40 and the conductive traces of Zone F.

Turning now to FIGS. 9 and 10, two diagrams illustrate the adaptation ofthe flexible portion 34 of the PCB to accommodate both six- andeight-conductor plugs. As described in U.S. patent application Ser. No.11/078,816 and further as shown in FIG. 10, the plug-jack interface isdisposed directly above the contact between the plug interface contacts24 and a flexible circuit board (or flexible portion of a circuitboard). These contact locations are approximately located on a straightline when no plug is installed (as shown in FIGS. 11 and 12) or when astandard eight-contact plug is installed. However, when a six-contactplug is installed (as shown in FIGS. 13 and 14), contacts 1 & 8 deflectmore than contacts 2 to 7.

The Zone A connection extensions 42 a and 42 h which connect traces 1and 8 to jack contacts 1 and 8 have been lengthened—as shown in FIG.9—and an “S” bend—as shown in FIG. 10—has been incorporated tofacilitate the additional deflection of contacts 1 and 8 compared to thedeflection of contacts 2 to 7 when a six-contact plug is installed inthe jack.

As shown in FIGS. 13 and 14, the longer connection extension 42 hassociated with the eighth trace allows for the greater deflection ofthe plug interface contact 24 h (associated with the eighth conductor)when a six-contact plug is inserted into the receptacle 22.

A preferred design of the mechanical and electrical connection of theflexible portion 34 of the PCB 32 to the plug interface contacts 24adjacent to and on the opposite side of the plug-jack interface 54 isshown in FIGS. 15-17. The connection is made by bending the free tips 56of the plug interface contacts 24 back on themselves, as shown in FIG.15, and by spot-welding two sections 58 and 60 of each contact togetheradjacent to the connection extensions 42 of the flexible portion 34 ofthe PCB 32. The connection extensions 42 are sandwiched between the twosections 58 and 60 of each contact. The spot-welding step as shown inFIGS. 16 and 17 may be performed with welding electrodes 62 a and 62 b.

Crimping and welding the contacts as described provides frictional forceallowing the plug interface contacts to grip the connection extensions42. As shown in FIG. 18, the plug interface contacts 24 may be providedwith gripping features 64 in the region where they contact the contactpoint via 48, beneath the plug-jack interface 54. The grip of the pluginterface contacts 24 on the via 48 can be enhanced by a number ofmethods such as coining, seriating, or abrading the contacts orroll-forming teeth on the contacts 24.

FIGS. 19 and 20 show an alternative way to connect a flexible printedcircuit board or a flexible portion 34 of a circuit board to a jackcontact. In this embodiment, the jack contacts are clip contacts 66 thatare provided with first and second bends 68 and 70. The connectionextensions 42 of the flexible portion 34 of a circuit board are heldbeneath the plug-jack interface by friction between the second bends 70of the clip contacts 66 and straight portions 72 of the clip contacts.

While the discussion above addresses the connection of a flexibleportion of a PCB to plug interface contacts, it is to be understood thatthis connection method may also be used with flexible printed circuits(FPCs) that do not contain rigid portions.

While the particular preferred embodiments of the present invention havebeen shown and described, it will be obvious to those skilled in the artthat changes and modifications may be made without departing from theteaching of the invention. The matter set forth in the foregoingdescription and accompanying drawings is offered by way of illustrationonly and not as limitation.

1. A crosstalk compensation apparatus for a modular communicationconnector comprising a jack and a plug, the jack having plug interfacecontacts, the apparatus comprising a flexible printed circuitmechanically and electrically connected at a first end to the pluginterface contacts, the flexible printed circuit mechanically andelectrically connected at a second end to network cable connectors andhaving circuit traces to compensate for near-end crosstalk (NEXT), theflexible printed circuit having a variable compensation zone thatreduces NEXT compensation as a communication frequency increases.
 2. Acrosstalk compensation apparatus for a modular communication connectorcomprising a jack and a plug, the jack having first through eighth pluginterface contacts, the apparatus comprising a flexible printed circuitmechanically and electrically connected at a first end to the pluginterface contacts via first through eighth flexible connectionextensions of the flexible printed circuit, wherein first and eighthflexible connection extensions of said flexible printed circuit arelonger than second through seventh connection extensions.
 3. Thecrosstalk compensation apparatus of claim 2 wherein said first andeighth flexible connection extensions of said flexible printed circuitare respectively connected to first and eighth plug interface contactswith an S-shaped bend.
 4. A crosstalk compensation apparatus for amodular communication connector comprising a jack and a plug, the jackhaving plug interface contacts, the apparatus comprising a flexibleprinted circuit mechanically and electrically connected at a first endto the plug interface contacts by clamping the flexible printed circuitbetween an end portion and an intermediate portion of each pluginterface contact at a clamping area of each plug interface contact. 5.The crosstalk compensation apparatus of claim 4 wherein portions of eachplug interface contact adjacent to the clamping area are weldedtogether.
 6. The crosstalk compensation apparatus of claim 4 whereineach of said clamping areas comprises at least one irregular surfacewhich contacts gripped portions of the flexible printed circuit.
 7. Thecrosstalk compensation apparatus of claim 4 wherein said plug interfacecontacts provide a clamping force on said flexible printed circuit atsaid clamping areas, said clamping force resulting from a separation ofsaid end portion and said intermediate portion of said plug interfacecontacts which are spring loaded together by the configuration of eachcontact.
 8. A crosstalk compensation apparatus for a modularcommunication connector comprising a jack and a plug, the jack havingplug interface contacts, the apparatus comprising a flexible printedcircuit mechanically and electrically connected at a first end to theplug interface contacts adjacent to and on the opposite side of theplug/jack interface, the flexible printed circuit mechanically andelectrically connected at a second end to network cable connectors andhaving circuit traces to compensate for near-end crosstalk (NEXT), theflexible printed circuit having a variable compensation zone thatreduces NEXT compensation as a communication frequency increases.
 9. Acrosstalk compensation apparatus for a modular communication connectorcomprising a jack and a plug, the jack having first through eighth pluginterface contacts, the apparatus comprising a flexible printed circuitmechanically and electrically connected at a first end to the pluginterface contacts adjacent to and on the opposite side of the plug/jackinterface via first through eighth flexible connection extensions of theflexible printed circuit, wherein first and eighth flexible connectionextensions of said flexible printed circuit are longer than secondthrough seventh connection extensions.
 10. The crosstalk compensationapparatus of claim 9 wherein said first and eighth flexible connectionextensions of said flexible printed circuit are respectively connectedto first and eighth plug interface contacts with an S-shaped bend.
 11. Acrosstalk compensation apparatus for a modular communication connectorcomprising a jack and a plug, the jack having plug interface contacts,the apparatus comprising a flexible printed circuit mechanically andelectrically connected at a first end to the plug interface contactsadjacent to and on the opposite side of the plug/jack interface byclamping the flexible printed circuit between an end portion and anintermediate portion of each plug interface contact at a clamping areaof each plug interface contact.
 12. The crosstalk compensation apparatusof claim 11 wherein portions of each plug interface contact adjacent tothe clamping area are welded together.
 13. The crosstalk compensationapparatus of claim 11 wherein each of said clamping areas comprises atleast one irregular surface which contacts gripped portions of theflexible printed circuit.
 14. The crosstalk compensation apparatus ofclaim 11 wherein said plug interface contacts provide a clamping forceon said flexible printed circuit at said clamping areas, said clampingforce resulting from a separation of said end portion and saidintermediate portion of said plug interface contacts which are springloaded together by the configuration of each contact.